Obsessive compulsive disorder. This?

Please help me with this Have i done something wrong I m 20 yr old nd having the problem of ocd. I m really very stressed i cannot live with it. When i was 10 or 11 i used to lie upside down and rub my penis as it gives me pleasure . Now i think at that piont of time i did same with my mother while my clothes were on means i was wearing clothes...now this has really stress me dat i have really done very wrong with my mother and cannot live my life.. i was not hit by puberty at at point of time....please help me .have i really done something very wrong???? Was it not normal at that age.......when i donot know what i was doing??please really help me. I cannot live futhur with this?? Have i done aomething wrong!!! Please tell